Agglomeration device
This invention relates to an agglomeration device or mixer such as shown in my prior U.S. Pat. No. 4,881,887 dated Nov. 21, 1989. 
     BACKGROUND OF THE INVENTION 
     Keeping material in an agglomeration device and out of the shaft bearing has been a difficult problem. End seals have been used wherein the material had to migrate against a centrifugal force generated by the rotating end plates which were slightly spaced from stationary end plates. 
     SUMMARY OF THE INVENTION 
     An object of the present invention is to overcome the abovementioned disadvantage of prior end seals by providing rotating metallic end rings on the rotating shaft sandwiched in fixed plastic rings with very close tolerances between stationary and rotating segments which, in combination with a labyrinth type of seal, prevents the abovementioned migration of material against a centrifugal force. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING 
     FIG. 1 is a partial vertical cross sectional view of an agglomeration device of the type shown in my prior patent which shows one of the end seals of the agglomeration device: the other end seal (not shown) being the same. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring more particularly to FIG. 1, numeral 1 denotes a rotating shaft of an agglomeration device on which rotating pins are mounted in staggered relationship. Ends 1a of the shaft 1 are of reduced diameter and rotate in piloted bearing 2 which is stationarily mounted to bracket 3 by pins 4, which bracket is integrally mounted on end plate 6 which houses a triple labyrinth seal 5. 
     Stationary steel drum 11 is rigidly secured to end plate 6 by seal 12 and has a cylindrical lining 10. In accordance with the present invention two fixed plastic rings 7 and 8 are rigidly attached to end plate 6, which rings are notched out adjacent shaft 1 to provide a space for a rotating steel ring 9 having a very close tolerance with both said rings and being rigidly secured to the rotating shaft 1 by set screws 13. Rings 7 and 8 are preferably of ultra high molecular weight, such as polyethylene, but they may be of any plastic material, such as polyurethane or Teflon. Ring 7 may be lubricated by grease injected through fitting 9 or by a nitrogen purge to further insure that material does not enter the labyrinth seal 5. 
     By virtue of the above described construction, material being rotated in the agglomeration device has been effectively prevented from entering the shaft bearing. 
     While I have illustrated and described a single specific embodiment of my invention, it will be understood that this is by way of illustration only and that various changes and modifications may be contemplated in my invention within the scope of the following claims.